Heatercraft uses a common core which I believe is Ford that can cheaply and easily be replaced at any radiator or auto parts store. There is not a whole lot available for boats, but using a common part is a good thing.

Many of the failures are actually installation errors where the hoses are not properly routed or supported, causing the core to crack where the fittings attach to the core. This happened to me and was a simple job of properly supporting the hoses and soldering the crack closed with a torch.

In colder climates you must drain the heater core to keep it from freezing but that is common sense.

I just had my third Heater Craft blow at 430 hours. Seems like each one lasts about 150 hours for me. Just love driving in 100 degree heat with 150 degree water on my feet.

Although CC will be replacing it again for no cost...its a pain. I am going to look and see where this one failed, seems like its at the fittings because the water was running down the hose to the carpet and not spraying under the dash. I agree with Peter that the hose support may be the issue for me.

Is there any reason I can't install a shut off valve for summer use?

And BTW...have you tried to find a radiator shop lately?...there are not too many left now that all the cars have plastic replace only radiators.

I just replaced my heater core, went out at 48 hours. And yes it is a pain to replace. My local radiator show told me they couldnt get one that size. I have the 3 vent box so its alittle longer than the 2 vent.

Yes you can just put shut-off valves on the inlet and outlet either at the motor (prefered as a line can blow and this will allow you to isolate the whole system) or at the heater. The motor just has plugs at the hose connections if you dont have a heater anyway so dont worry about flow issues.

I installed an old escort heater core and a fan I bought from lowes in my old boat. I never had a problem over five years of use. The thing is, I don't want to have to go through all of that again, I just want to purchase one and install it.

If the connections to the core are the problem, I'll probably just weld on some reinforcement prior to installing it. Downside to this little customizing will more than likely mean no warranty.

It sure would be nice if they just built the thing to last in the first place.

They do, you just have to install it correctly and support the hoses properly so they don't put any extra force on the core housing. If everything is supported well and the install is tight it shouldn't break!

I agree with all the comments about proper installation. I've blown through more than I can count but I think I've got it nailed now. The hoses are firmly attached to the hull of the boat before they go into the core. The pain in the arse part about replacing them is that you have to drill out all the rivots just to get to the common auto store component. Next time mine blows (and it will-I have no wood to knock on now), I'm replacing all the rivots, i.e., threading the wholes, etc.